Big Gay 2F Build Tech (1 Viewer)

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Small block Chevy valve springs go right in place of the stock 2f springs. When I tested mine on a Rimac (valve spring checker) they were like 25lbs closed and 45-50 lbs open. STOCK small block chevy springs off an old head laying in my backyard with rust on them were like 45-55 closed and 70-ish open IIRC.....

It was cheap enough at the time I had my head off...


On balancing the lower end, If you have the time and $$$ I would do it... The 2f isnt known for being balanced stock... Measured in OUNCES so Im told.... (should be like 1/2 a gram) Wastes energy and stresses parts at that level...


Nice thread BTW


Chris:cool:
 
DHONDAGOD said:
Small block Chevy valve springs go right in place of the stock 2f springs. When I tested mine on a Rimac (valve spring checker) they were like 25lbs closed and 45-50 lbs open. STOCK small block chevy springs off an old head laying in my backyard with rust on them were like 45-55 closed and 70-ish open IIRC.....

It was cheap enough at the time I had my head off...


On balancing the lower end, If you have the time and $$$ I would do it... The 2f isnt known for being balanced stock... Measured in OUNCES so Im told.... (should be like 1/2 a gram) Wastes energy and stresses parts at that level...


Nice thread BTW


Chris:cool:
Click to expand...

Do you have to go with SBC valve springs when doing the RV cam? Or is it more of a better performance gain?
 
matt.mcinnes said:
Colour is :cool:

Can I have the paint code:D
Click to expand...

http://www.duplicolor.com/products/metalcast.html

Using ground coat first then the metal cast on top.

Very gay.
cans_metalcast.jpg
 
Marshall, I would go with whatever MarkW recommends. I know MAF makes that statement about the "Rediculous overlap" but there is a reason for that. It has been discussed here before, but I can't recal exactly. I think it has to do with the torque peak and rpms.
I went with a stock grind cam on the basis that Toyota thought it best. I operate at no more than 3-3,500 rpm tops and cruise at no more than 3K so a cam with performance above that is of no use in my applicarion. I was amazed that at the BHCC I almost never revved above 1,500 rpm.
If you are looking at more highway speeds than wheeling, then your choice will probably be different than mine.


My .02? Stock grind cam and get the CCOT lifters, or resurface yours.:beer:


ed
 
Same boat

This is a great thread and very timely. I'm currently going through the same engine rebuild parts evaluation process for my '75 2F looking at the various options from different suppliers for cams, pistons, rings, etc. At this point, I'm still compiling prices from CCOT, SOR, OEM and MAF. I've read the posts on the MAF billet RV cam and forged pistons but haven't made a final decision yet on which way to go -- OEM vs. Performance. If I go the performance route, it seems like a slippery slope with porting and polishing the head along with additional parts required to realize the full potential of the non-OEM components -- header, new distributor, new carb, upgraded wires, better radiator, oil cooler, etc. Does it make sense to upgrade the pistons, rings and cam now since I'm replacing them anyway and upgrade the other bits and pieces as time and $$$ permit?
 
From what I've read, stock valve springs are good for over 5000 rpm.
 
Quote from a PM from Mark W.

262 advertised duration.


Mark...

Thanks Mark. Do I need to buy SBC springs with this cam?


I normally run stock springs with this cam. You need to be careful about shimming them. they are running close to the limit and if you shim them much at all you may stack them. But I have found that even worn and "weak" stock springs do the job just fine within the rpm limits that you are working with for the 2F.

Mark...





Now I just need to figure out what shimming is. lol
 
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One more thing. Just got through talking to the well respected machine shop here in town about balancing the engine. He said I would just be wasting money if I did that. I told him what people had said here and it didn't phase him. Said that since it wasn't an auto the flywheel didn't need to be balanced and since I was just reringing and puting new bearing that it would be just fine at 5000k rpms since I was not changing the stock rotational mass that was balanced at the factory. Is this true? I could see wanting this for an early 2f or f but didn't they pay closer attention to the 2f's in FJ60s when it came to engine balancing?

Anyway if you want to read up on balancing this is a good place.

http://www.aa1car.com/library/2003/eb10330.htm
 
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Alright now you have got me what is shimming the springs? My machine shop did the valves. They and the springs are already together. Is this wrong? Sorry for all the questions.


Springs tend to weaken with age. There is a specified pressure that they are supposed to hold against the seat when the valve is closed. To bring this back into spec with used springs it is common to put shims under the springs so that they pull the valve shut a little tighter than they would without them. These shims cause the spring to be compressed a little more. This means that there is less room for more compression (as the valve opens) before they run out of room and fuly compress (stack).

It is not wrong, but with a high lift cam the loss of compression room for the spring may become a problem.


Mark...

This is good stuff.

So should I just buy new SBC springs and be done with it? Any particular type.

Thanks again.


I'd stick with the stock springs. I've never had a problem with them, even with runs to 5000 and a bit higher.

Not counting shipping, Delta will regrind your cam for about $90 IIRC. If you have damaged lobes that have to be welded up it costs a little more for each lobe that they do. Turn around is only a couple of days.

A new MAF cam, not a regrind, that is an advantage over a regrind. I use regrind in almost all of my engines, but a new billet will have a slightly larger base circle and put slightly less stress on the lobes and lifter faces.

Don't forget that you need new or reground lifters too.


Mark...
 
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Trollhole said:
One more thing. Just got through talking to the well respected machine shop here in town about balancing the engine. He said I would just be wasting money if I did that. I told him what people had said here and it didn't phase him. Said that since it wasn't an auto the flywheel didn't need to be balanced and since I was just reringing and puting new bearing that it would be just fine at 5000k rpms since I was not changing the stock rotational mass that was balanced at the factory. Is this true? I could see wanting this for an early 2f or f but didn't they pay closer attention to the 2f's in FJ60s when it came to engine balancing?

Anyway if you want to read up on balancing this is a good place.

http://www.aa1car.com/library/2003/eb10330.htm
Click to expand...


Balance it, Toyota did not balance their engines at this time as well as they could have.

My 2c
 
Trollhole said:
Do you have to go with SBC valve springs when doing the RV cam? Or is it more of a better performance gain?
Click to expand...




I did the SBC springs because:

1. I had my head apart on the bench

2. I have a Rimac (spring tester) and found the stock springs to be silly weak

3. I have several stock SBC heads laying around to rob springs off and compare to the stock 2f springs.

4. SBC springs were the same size as the Toy springs and higher pressure without getting silly.

5. SBC springs (old, unknown mileage/age) were free and still an upgrade from the Toy spring

6. Motor runs "crisper" and revs-out quicker now...


Other than a milled head and light bowl work in the ports, header and non-factory carb, my motor is stock. Unknown mileage.

For the cost and benifits I reccomend doing it...



As for balancing, If you have the money, DO IT! ESPECIALLY if your going to wind the thing out!


Chris:cool:
 
Well I'm looking at around doing 5000rpm max. Is that winding it out?

Is it possible to just get all the rods and pistons to be the same weight or does the crank come into this equation?
 
Trollhole said:
Is it possible to just get all the rods and pistons to be the same weight or does the crank come into this equation?
Click to expand...

You'll want to balance the whole rotating assembly...crank, rods pistons...
 
Thought so.

Well it looks like I have nailed down a spare MAF billet RV cam from a MUD member. So I'm golden for the cam. Will be tearing into the bottom end this weekend. Will post pics of the progress.
 
Those colors put me in the mood for Christmas! :mad: s***! that'll be here before ya know it...
 
This purple attire belongs to a smoothie I know :grinpimp:
cs130%2520%2528Custom%2529.JPG
 
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